I have published my GB Player implementation for VBA-M: github.com/illinx/visua... With this enabled, VBA-M will perform the GBP handshake for supported games, allowing alternate color palettes and rumble support. Rumble is implemented using the rumble backend that already exists for GPIO rumble
GitHub - illinx/visualboyadvance-m at sio_rumble
This is my personal fork of vba-m for projects such as SIO Local, GBP Support, and GBA2 - illinx/visualboyadvance-m
github.com